photo courtesy National Park Service. Department of the Interior

According to the Center, the population of Sierra Yellow legged frogs has decreased by 75% in recent decades. Reading about these frogs, we were struck by how they are a symbol of the challenges that frogs face worldwide. But they aren’t facing one challenge—they seem to be facing almost all of them:

Introduction of nonnative species: Stocking of nonnative trout in high-elevation Sierra lakes has been the main cause of the species’ decline. The trout eat tadpoles and juvenile frogs and alter the food web of the aquatic ecosystems on which the native frogs depend. The Department is recommending no trout stocking in the state without a fish management plan, and no further stocking of trout in areas that would conflict with protecting yellow-legged frogs.

Pesticides: Recent research has linked pesticides that drift from agricultural areas in the Central Valley to declines of native amphibians in the Sierra Nevada. Pesticides and other pollutants can directly kill frogs and also act as environmental stressors that render amphibians more susceptible to diseases, including a chytrid fungus that has recently ravaged many yellow-legged frog populations.

Loss and degradation of habitat: Grazing, logging, water diversions, off-road vehicles and recreational activity are allowed in frog habitat.

Climate change: Climate change has brought warmer temperatures, decreases in runoff, shifts in winter precipitation in the Sierra from snow to rain, and habitat changes that are rendering frog populations more vulnerable to drought-related extinction events.

A recent settlement agreement with the Center for Biological Diversity, which will also speed protection decisions for 756 other species, requires the U.S. Fish and Wildlife Service in 2013 to make a decision about whether to add the Sierra frog to the federal endangered list.

See the Center for Biological Diversity for more information about these frogs and about the other endangered species they are working to protect.

Painted Hula Frog from Y Net News Website

Here’s the story of the hula painted frog, from Conservation International’s website:

The frog was discovered in Israel’s Lake Hula, one of the world’s oldest documented lakes, which provided fertile hunting and fishing grounds for humans for tens of thousands of years.

In the early 1950s, the lake and surrounding marshes were drained as a way of tackling malaria. But the costs for doing this were high. Among other environmental problems, draining the lake led to the near extinction of an entire ecosystem and the unique endemic fauna of the lake, including the Hula painted frog. Ironically, species such as the painted frog feed on mosquitoes that carry malaria.

Concern over the draining of Hula grew among the people of Israel, leading to the formation of the Society for the Protection of Nature in Israel and a movement to reflood the Hula Valley. It took 40 years for the protesters’ voices to be heard, but in the mid 1990s, parts of the valley were reflooded.

While much of the ecosystem was restored, not all species re-appeared and it was believed to be too late for the Hula painted frog; the species was declared extinct in 1996 by the International Union for the Conservation of Nature (IUCN). The frog became a poignant symbol for extinction in Israel.

Only three adult Hula painted frogs had ever been found. Two of these were collected into captivity in the 1940s, but the larger one ate the smaller one, leaving just one specimen to remember the species by.

The enigmatic frog was selected as one of the “top ten” species during the Search for Lost Frogs last year, highlighting the global importance of this species. It was lost but not forgotten.

Recently, however, Nature and Parks Authority warden Yoram Malka was conducting his routine patrol of the Hula Nature Reserve when something jumped from under him. He lunged after it and caught it: he was holding in his hand the first Hula painted frog seen since the 1950s.

To quote the CI site:

This rediscovery is the icing on the cake of what is a major victory for conservation in Israel: the restoration of a rare and valuable ecosystem. Because Israel has given the Hula Valley a second chance to thrive, the Hula frog has gone from being a symbol of extinction to a symbol of resilience.

Mazel tov, Dr. Moore! And thanks, Rachel, for reporting the story.

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